376 DISEASES OF THE HEART. 



rise to fatty degeneration of its walls. Finally, in many cases of val- 

 vular disease, with consecutive hypertrophy, a partial fatty metamor- 

 phosis takes place. 



The origin of this " spurious hypertrophy " is somewhat obscure, 

 and almost without parallel ; while fatty degeneration of the cardiac 

 muscles, in consequence of defective nutrition or pressure, etc., finds 

 many analogies in the metamorphosis of other organs whose nutrition 

 is impaired. 



3. Amyloid degeneration^ according to Rokitansky, occurs espe- 

 cially in the hypertrophied right side of the heart, causing its cut sur- 

 face to resemble that of a piece of bacon, and occasioning great rigid- 

 ity of its wall. The sarcolemma is filled up by nodules, which glitter 

 dimly and show the peculiar reaction of amyloid degeneration, turning 

 blue upon application of a dilute solution of iodine and weakened 

 sulphuric acid. 



4. Cancer is very rare in the heart, occurring only in general can- 

 cerous infection, or by extension from the mediastinum or pericardium. 

 It forms circumscribed tumors, usually of the medullary, or else of the 

 melanotic kind, which project either inward or outward, and may 

 sprout into the cavity of the organ. In other cases, especially where 

 propagated from cancer of neighboring parts, wide tracts of the sub- 

 stance of the hearts become transformed into cancer (infiltrated cancer, 

 see cancer of the lungs). 



5. Tubercles scarcely ever occur in the heart. Yellow, cheesy 

 nodules, sometimes found embedded in its walls, are not to be regarded 

 as tubercles, and shall be accounted for when we come to treat of 

 pericarditis. 



6. Parasites. The cysticercus has been found in the heart, enor- 

 mous numbers of them existing at the same time in other muscles of 

 the body. The echinococcus has also been met with. 



SYMPTOMS AND COURSE. Relaxation of the cardiac substance, after 

 typhus, exanthematic disease, etc., of course reduces the efficience of 

 the organ, and is very apt to occasion dilatation. It is only in the 

 latter case that we are able to recognize it with certainty. If, after an 

 attack of some exhausting disease, we find that the impulse of the 

 heart is extraordinarily feeble, the area of cardiac dulness having in 

 creased, we may also attribute the small pulse, the dropsical aspect, 

 the spontaneous coagula in the veins, in part, at least, to the structural 

 changes which the substance of the organ has undergone.* 



If the existence of dilatation cannot be proved, we must remain in 



* In such instances cyanosis is rare, as the volume of the blood is reduced and 

 its quality is very poor; so that, even though it vrere to overfill the veins, it would not 

 give rise to the bluish complexion. 



